Been watching frozen planet, ideas for frostfell game ensue

[Mummy king]

David Attenborough's frozen planet recently started on BBC, and whilst watching it I was fascinated by the way orca hunt, and wanted to work this into an encounter for a frostfell-based mystery game. At some point the players will be ambushed or lured onto an ice floe, where they will drift out to sea and be attacked by a pod of killer whales. The aspects of the orca hunt I would like to work into game terms are;
1) Teamwork. Orcas have the most complex hunting behavior ever observed. (This will be done through tactics, natch)
2) Using the water. Orcas swim in unison to create waves which knock prey off ice floes into the water, they also exhale underwater and create turbulence and obscure themselves from prey.
3) Dragging prey underwater to drown it. (This one is easy, grapple checks)

Other aspects I am thinking of including are the bull orca being "special" in some way, either through the use of a template or just advancement, and the orca pod being under the direction of a wavekeeper druid.

I'd appreciate any suggestions anyone has for ways to mechanically interpret these aspects of behavior or other ways to make this encounter memorable.

[hamishspence]

Creating waves to move a target might be a variant of Bull Rush.

[Mummy king]

Creating waves to move a target might be a variant of Bull Rush.

Maybe the orcas make a swim check, for each one that succeeds the DC to resist the bull rush increases by 2, standard penalties for ice/unstable ground apply. Sound reasonable?

[hamishspence]

could work- maybe stat it out and see what the chances an average Str Medium-sized creature has of resisting it- see if you think it's overpowered?

[sirpercival]

The orcas are dungeoncrashers, right???